code: def test_non_fitted_error(df_vartypes):
      with pytest.raises(NotFittedError):
          transformer = PowerTransformer()
          transformer.transform(df_vartypes)
  
file_path: feature_engine/tests/test_transformation/test_power_transformer.py
imports: import pandas
  import pytest
  from sklearn.exceptions import NotFittedError
  from feature_engine.transformation import PowerTransformer
label_desc: Use image node_id 5 for calling a global function with example usage: test_non_fitted_error(df_vartypes) without return types